Man develops rare allergy to red meat

If you've been spending a lot of time outdoors and have suddenly developed an allergy to red meat, you may want to check yourself for ticks. The Lone Star tick can set off a potentially life-threatening red meat allergy.

That's what happened to outdoorsman and arborist Bill Armstrong from Tulsa, Oklahoma. He told CBS Tulsa affiliate KOTV that he didn't remember any ticks biting him, but a severe allergic reaction after eating a taco last fall prompted him to seek medical attention.

Doctors can be slow to recognize the problem, and Armstrong's trip to the ER failed to provide him with answers. After a second reaction to eating a cheeseburger a few days later, the avid carnivore went to an allergy clinic for testing.

"They said, 'oh, well, you're allergic to red meat.' And I asked, I said, 'Are you sure you're looking at the right person? Because that's what I've lived on my whole life.' And they said, 'Yeah, this is you,'" Armstrong said.

The Lone Star tick, found in the South and the eastern half of the United States, carries a sugar called alpha-gal that humans don't have. This sugar is also found in red meat -- beef, pork, venison, rabbit, and some dairy products. When the tick bites, it can trigger a person's immune system to create antibodies to the sugar that, in turn, cause their body to reject red meat, setting off a serious allergic reaction.

And, because the slightest cross contamination could be fatal, dining out can become a matter of life and death for those affected.

Armstrong is now restricting his diet to "fins" and "feathers" - just fish and poultry.

"Seafood's not bad, but there's only so many ways you can cook chicken and turkey," Armstrong said laughing.

Armstrong, and others affected by the allergy, have reason to hope for a time when they can reintroduce red meat into their diets. Doctors have yet to confirm if the allergy is permanent, and there is a chance some people will grow out of it. But, be warned, if you get another tick bite, the allergy will return along with the severe symptoms.

Though Armstrong's reaction occurred almost immediately, the symptoms can take up to eight hours to show up after ingesting red meat, in some cases. Allergic reactions can be treated with antihistamines to ease itching. In case of an extreme reaction, Armstrong carries a medicine kit with an EPI shot.